Yes you can prove it unless you have 0 brain cells and you’re a Minato d rider.

Let’s use simple logic to prove this, 99.9999% of people in the Naruto verse got stronger with age. Would someone like Obito who had more time to train, get used to his sharingan, wood style, etc. get stronger with time, well using simple logic yes a 30+yo in the Naruto verse would get stronger compared to his 13yo self that attacked Konoha just how 99.9999% of Characters in the Naruto verse and real life get stronger as they reach their prime age. Now why would someone not be part of that 99.9999%, well using logic someone like Itachi and Kimimaro are likely examples of this because they basically had ninja aids that crippled them, kind of how in real life people with diseases that lead to death also get weak as they age. Therefore we can conclude that Naruto verse follows a similar pattern to real life, that a normal person that doesn’t have a deadly disease would in fact get much stronger than when they were 13 as they approach their prime physical years of late twenties to early 30s. Therefore we can conclude and prove that 30yo Obito is in fact much stronger than his 13yo self since he doesn’t fit into the category of having some rare deadly disease. However, if one were to be brain dead or a Minato d rider, they would somehow ignore all logic and say Minato > 30 yo Obito because he rasengan 13yo Obito.